Silicon
METALLOID
Bohr Model: Electrons arranged in energy shells around the nucleus.
Silicon is a chemical element with symbol Si and atomic number 14. It is a tetravalent metalloid, more reactive than germanium, the metalloid directly below it in the table. Controversy about silicon's character dates to its discovery.
Quick Facts
Atomic Number 14
Period 3
Group 14
Phase Solid
Appearance crystalline, reflective with bluish-tinged faces
About Metalloids
Metalloids have properties intermediate between metals and nonmetals. They often act as semi-conductors, making them essential for electronics.
History
Discovered By Jöns Jacob Berzelius
Named By Thomas Thomson (chemist)
Physical Properties
Atomic Mass 28.085
Density 2.329 g/L
Molar Heat 19.789 J/(mol·K)
Phase Transition (Melting & Boiling Points)
Silicon melts at 1687 K and boils at 3538 K.
Atomic Properties
Electron Config [Ne] 3s2 3p2
Electronegativity 1.9
Electron Affinity 134.0684 kJ/mol
Ionization Energy 786.5 kJ/mol
Orbital Filling Diagram
This diagram visualizes electron configuration according to the Aufbau principle and Hund's rule.
Boxes represent orbitals (s, p, d, f), while arrows indicate electrons with spin up or down.
Electrons fill lower energy levels first and occupy orbitals singly before pairing.
Emission Spectrum
Photograph
External Resources
Study Guide
Atomic Number
The number of protons in the nucleus, which defines the element.
Atomic Mass
The average mass of an atom, including protons and neutrons.
Electronegativity
A measure of how strongly an atom attracts electrons in a bond.
Ionization Energy
The energy required to remove an electron from an atom.
Electron Config
The arrangement of electrons in the atom's energy shells.